I would love to say it has non of what you mentioned, but it has a little bit of everything except incest at the beginning (can't remember well bc I read this since it came out). But it's a very well written story and there are good character developments. I wouldn't say anyone was acting childish here, and about age gaps... there is one in 3rd season because it's a story about side couple's past life and I'm guessing there was an age gap between them in that story. But well aging here is complicated whatsoever because it's about reincarnations and different creatures like reapers and goblins that came on Earth from underworld, but overall there are no huge age gaps, not in their present lives. Hope that helps a bit and if I said something incorrect, anyone pls correct me (=・ω・=)
is this worth reading? does this have any sa, rape, incest, miscommunication, manipulation, red flag, toxic people? is the plot good? is it an immature relationship where they behave like fucking children and also think like one? big age gap?